Composite materials are more commonly being used for fabrication of a wide variety of components. For example, carbon fiber composites have high strength and a low weight, making carbon fiber composites attractive for use in aviation applications that require these functionalities. As another example, ceramic matrix composite (CMC) materials can withstand relatively extreme temperatures; accordingly, there is particular interest in replacing components within a combustion gas flow path of a gas turbine engine with components made from CMC materials. Many composite materials, such as carbon fiber and CMC materials, are formed into plies of the composite material, and the composite plies may be laid up to form a preform component that may then undergo various processing cycles to arrive at a component formed from the composite material.
Typically, composite components formed from plies of the composite material comprise many composite plies. Each ply is cut from a sheet of the composite material, and then the cut composite plies are laid up to form one or more ply stacks that form the component preform. Often, the cut plies are manually removed from the sheet and manually placed in a ply storage area or manually stacked. Thus, the handling and forming of composite preforms is a time consuming and labor intensive process, which increases the cost of the part.
Automating the removal and storage or stacking of the preform process could reduce the part cost and cycle time, as well as reduce employee health concerns from the repetitive nature of ply removal and handling. However, several barriers must be overcome to automate the process of removing composite plies from the sheet of composite material and moving the plies either to a ply storage area or for stacking. For example, to maximize material usage and minimize material waste, a variety of ply shapes and sizes are nested within the composite sheet and then cut prior to removal. Therefore, an automated apparatus for removing the composite plies must be able to adapt to a variety of ply shapes. Also, the automated apparatus must be able to remove the composite ply from the nested plies without displacing the skeleton or remaining composite sheet material. As another example, for large composite plies, the automated apparatus must be able to maintain tension on a ply as it is removed and moved to prevent damaging the ply as it is removed or moved.
Accordingly, an automated ply manipulation apparatus would be desirable. For example, a ply manipulation end effector for a robotic arm would be beneficial. In particular, a ply manipulation apparatus with features for automatically adjusting a position of grippers used to pick up a ply would be useful. Additionally, a modular ply manipulation tool for adapting to a plurality of ply shapes and/or sizes would be helpful.